In the coffee brewing art, one type or class of commercial coffee brewing machine is most commonly used. Machines of the referred to class of machines comprise flat, horizontal bases with front, rear and side edges and horizontal upwardly disposed trays upon which one or a pair of coffee decanters can be set and which are oftentimes provided with electric heating elements to maintain the coffee filled decanters warm. These machines next include vertical columns projecting upwardly from the rear sides of the bases and have forwardly projecting heads on the upper ends of the columns, overlying the bases and the upper open ends of the decanters supported thereby. The heads carry hot water supplies which hold predetermined volumes of hot water sufficient to brew one batch or full decanter of coffee. The hot water supplies have water discharge openings or ducts opening at the bottoms of the heads, above and in vertical alignment with the decanters arranged on the trays to receive brewed batches of coffee. In some of these machines, the water supplies must be manually filled with hot water through access openings at the tops of the heads while in other machines, the hot water supplies includes means to automatically replenish the supplies of water and electric resistance heaters to suitably heat the water.
The heads of the above noted class of machines have flat horizontal downwardly disposed bottom walls, or equivalent structure, with vertical through openings through which the water discharged by the hot water supplies is free to flow, or into and through which the discharge ducts of the water supplies freely project. The bottom walls, or equivalent structure, of the heads have a pair of elongate horizontal laterally spaced parallel brew rails which extend fore and aft and occur in limited predetermined spaced relationship below those bottom walls or structure. The brew rails occur at opposite sides of the water discharge and through openings and slidably receive and support opposite side portions of rim flanges at the upper ends of upwardly opening cuplike brew cones. The brew cones carry predetermined measured volumes of roasted and ground coffee beans, sufficient for brewing one batch. The upwardly opening cup-like brew cones have bottom walls with central coffee discharge openings which occur in spaced vertical relationship above the open upper ends of coffee decanters positioned on the trays of the machines to receive fresh brewed coffee.
In operation, when a batch of coffee is to be brewed, a brew cone containing a measured volume of ground roasted coffee beans (hereinafter called "ground coffee") deposited therein is slidably engaged with the brew rails and is supported thereby beneath the head of the machine, to receive hot water discharged by the hot water supply and a decanter is arranged on the tray of the machine to receive freshly brewed coffee flowing from the cone. When the cone and decanter are thus arranged, the supply of hot water is caused to flow from the head into the cone. The water percolates down through the bed of ground coffee beans within the cone, extracting flavor and essence therefrom. The coffee brewed within the cone flows out through the opening in the bottom thereof and into the decanter.
The above noted class of brew machines have become substantially standardized with respect to the volumes of coffee brewed each time the machines are operated and with respect to the volumes of ground coffee beans that must be used for the effective operation of the machines and the brewing of satisfactory batches of coffee; that is, brews of coffee which have desirable and acceptable flavor, aroma, texture and color.
As a result of standardization of the foregoing noted class of coffee brewing machines, there are two basic sizes of machines; one size being especially designed and operable to make ten 6 ounce cups or 60 ounce batches of coffee and the other size being especially designed and operable to make eight 6 ounce cups or 48 ounce batches of coffee. The larger ten cup machines are provided with large brew cones especially designed and serviceable to receive and hold approximately 21/2 ounces of ground coffee while the smaller eight cup machines are provided with small brew cones especially designed and suitable to receive and hold approximately 11/2 ounces of ground coffee. A further result of standardization of the noted class of machines is that the lateral displacement, length and vertical placement of the brew rails for the larger ten cup machines and the vertical extent of the brew cones for those machines have become standardized. The same is also true in the case of the smaller brew cones for the most common makes of eight cup machines. The brew rails for the eight cup machines are shorter and closer together and the brew cones for those machines are narrower than the brew rails for the larger ten cup machines, with the result that the larger ten cup machines, of like make, will not receive and support the smaller brew cones and vice-versa.
The machines referred to above became standardized when coffee beans were in plentiful supply, inexpensive and when roasting and grinding of the beans could be and were based upon what has become an extravagant and uneconomical use of beans.
As a result of oftentimes limited supplies of coffee beans and as a result of the present and increasing high cost of coffee beans, the producers of roasted and ground coffee beans are now producing what is referred to as "high yield" coffee. High yield coffee is such that a greater number of cups of good and acceptable coffee can be brewed from a lesser quantity of ground coffee than was previously possible.
To make high yield coffee, the beans are roasted and blended differently, are sometimes ground differently and the grindings are oftentimes rolled or pressed into a flake-like condition, whereby extraction of the flavors and essence therefrom is notably enhanced when the brewing of coffee therewith is carried out.
While 21/2 ounces of regular ground coffee is required to brew ten 6 ounce cups or 60 ounces of good and acceptable coffee, it is possible to brew an equal volume of comparable coffee with but 2 ounces of high yield ground coffee. The economic savings to be gained through the use of extended ground coffee (compared with the use of regular ground coffee) is apparent and can add up to substantial cost savings or increased profit in commercial establishments where large volumes of brewed coffee are sold.
Two ounces of high yield ground coffee in the large brew cones for ten cup brew machines may not be satisfactory since those cones are large in diametric extent and define a large effective surface area over which the ground coffee must be deposited. Due to the large effective surface area of such cones, 2 ounces of extended coffee establishes a bed of ground coffee which is too thin or shallow to allow for effective percolation of hot water therethrough and the effective extraction of the flavor and essence therefrom.
In order to effectively brew ten cups of coffee with 2 ounces of high yield coffee, the bed of ground coffee through which the hot water is percolated must be considerably deeper than the bed such a volume of coffee can establish in a brew cone designed to effectively receive 21/2 ounces of ground coffee.
The inventor of the present invention determined that a small or eight cup brew cone, for eight cup coffee brewing machines, which is designed to effectively hold 2 ounces of regular ground coffee would be most effective to produce ten cups of coffee if such a brew cone were to be made to fit a twelve cup brewing machine or if a ten cup brewing machine was modified and made to accept a 2 ounce or eight cup brew cone. It was then determined that to make and effect distribution of special, small brew cones, adapted to receive 2 ounces of ground coffee, for large standard ten cup machines, or to modify existing or make new ten cup machines to accept standard, small, eight cup or 2 ounce brew cones, would be economically prohibitive and impractical. As a result of the above, it was determined that an adapter effective to relate a small standard eight cup brew cone with a standard, large ten cup coffee brewing machine was needed.